Author: Hannes Baumann

Shell recycling will help restore oysters in Long Island Sound

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On 6 October, Research Professor Z.Baumann surveys the wild oyster reef at Morris Creek, CT

By Elaina Hancock.

7 November 2022. An unexpected find of a healthy, well-established oyster reef tucked away in a shoreline park inspired UConn Marine Science researcher Zofia Baumann to study ways to help these vital ecosystem engineers make a comeback.

Oyster habitats were largely destroyed by development, over-harvesting, and pollution, but in Long Island Sound, their numbers might be on the rise. Baumann and others hope to help restore Connecticut’s oyster populations.

Oysters build habitats where many species flourish, they improve water quality and make shorelines more resilient to erosion, but they need old shells to start building on. The site that became the focus of the project is one where oyster shells were deposited. Unfortunately, there is a shortage of shells in Connecticut and addressing this problem is the primary goal.

The project brings together members of the community, shellfish farmers, and regulators, as Baumann says, this effort relies on the community, otherwise, it will not work.

A soccer match to honor Dennis Arbige’s service for DMS

23 September 2022. On this day, we honored the long years of service of Dennis Arbige, who is officially retiring as the building manager this summer (he’s still very much around, helping with the transition). We all know Dennis as the kind force keeping the wheels from falling off of our beloved building, battling with environmental chambers, autoclaves, and a gazillion other things, while coordinating many of the various upkeeps over the years. But Dennis is also a gifted electrician and underwater technology buff, who has accompanied several ROV missions in the past.

And in addition, many of us simply love Dennis as the cornerstone of one of DMS’ most sacred traditions: the Friday afternoon co-ed soccer game!
For that reason, we planned to celebrate Dennis’ service this Friday in style!

Best of luck, Dennis, for your next move in life.
Please, if you can, keep playing soccer with us!

on 23 September 2022, DMS, Avery Point faculty, staff and students celebrating with Dennis (with ball)

The Arctic is not so Boron!

Professor Penny Vlahos investigates what happens with the ocean chemistry at the marginal ice zones in her recent publication

By Ewaldo Leitao.

The Arctic Ocean is undergoing rapid changes due to climate change. Increasing temperatures result in decreasing sea-ice extent, constant decreasing and thinning of permanent sea-ice caps. Some projections even show a completely ice-free Summer by 2050!

Another consequence of climate change is ocean acidification due to increasing atmospheric CO2. That leads to the decrease in water pH and changes in carbon chemistry dynamics. The Arctic may be a small ocean (3% of total oceans area) but it has an important contribution to carbon uptake (10%). Therefore, it is necessary to understand the impact of these changes across the oceans, including the Arctic, in order to be prepared for it.

Some chemical elements, such as boron, contribute to the ocean’s capacity to resist changes in pH, that is ocean’s alkalinity. Boron, in combination with salinity, has been used as a universal rule in the open ocean (boron to salinity ratio) in order to understand the contribution of boron to alkalinity, and therefore ocean carbon chemistry. But how does that change in the less saline areas, such as the marginal ice zones of the Arctic?

In the recent paper published in Nature Communications, Prof. Penny Vlahos and graduate student Lauren Barrett observed that, when measured in low salinity areas (marginal ice zones), the boron to salinity ratio deviates from the expected in open oceans. In a cruise that took place in May of 2021 (you can read more about the cruise here), researchers were surprised to find significant deviations in the boron to salinity ratios in ice and brine samples. Lower water temperature and lower salinity alters the exchange between boric acid and borate, which is used to determine the contribution of boron to sea water alkalinity (capacity of water to resist changes in pH and acidification), driving this deviation of the boron to salinity ratio compared to open ocean waters.

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Prof. Penny Vlahos (right) with graduate students Lauren Barrett (left) and Emma Shipley (middle) on board the RV Sikuliaq

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Stations sampled on the RV Sikuliaq between May 20th to June 14th, 2021.

The unique microenvironment of the marginal ice zones creates a very dynamic system. As seawater freezes, salts are rejected, but there is still a liquid region between ice crystals, called brine channels. These channels allow boron to undergo inorganic changes that may result in the variations observed in some of the samples, increasing the variability of boron to salinity ratio observed in these Arctic areas.

Prior to boarding the research vessel, researchers had to quarantine for two weeks. But this was a valuable time to Lauren Barrett. “Over quarantine I spent a lot of time reading about the various uncertainties that other authors encountered in accurately and precisely constraining the carbonate system in this highly heterogeneous environment. The boron to salinity ratios that we present here warn against applying universal ratios constrained in the open ocean to marginal ice zones and ice environments.” says Lauren.

Penny Vlahos Arctic
Lauren making a snowman at one of the stations that was ice covered, with the RV Sikuliaq on the back.

Lauren also shared a little bit about her experience: “I am very grateful for the opportunity to work with our international coauthors. The collaborative and interdisciplinary nature of marine science is one of my favorite aspects of working in this field. This research cruise was a great experience both personally and professionally, and I continue to be grateful to work in a field where cruising and getting to see polar bears is all in a day's work.”

The Arctic is an important sink of carbon and yet highly susceptible to climate change. Therefore, understanding detailed information of this system, instead of applying universal ratios, is necessary in order to better understand the carbon chemistry of the Arctic and be prepared for the consequences of climate change.


Vlahos, P., Lee, K., Lee, CH., Barrett, L, and Juranek, L. (2022) Non-conservative nature of boron in Arctic marginal ice zones. Nature Communications Earth & Environment 3, 214


Prof. Rob Mason presented with Lifetime Achievement Award

July 2022. DMS is proud to announce that Prof. Rob Mason was presented with a Lifetime Achievement Award during this years ICMGP2022 (International Conference on Mercury as a Global Pollutant). A big, heartfelt congratulations to this award, Rob!

Here is what the awarding committee said about Prof. Mason lifetime achievements:
Cross-posted from ICMGP2022

Dr. Robert (Rob) Mason has been a professor of Marine Sciences, with a joint appointment in Chemistry, at the University of Connecticut (UConn) since 2005. Prior to his current position he was a faculty member at the Chesapeake Biological Laboratory, part of the University of Maryland Center for Environmental Studies, from 1994 to 2005. After graduating from UConn in 1991 with a PhD in Marine Sciences, under Dr. Bill Fitzgerald, he completed a post-doc at MIT in Cambridge, Massachusetts working with Drs. Francois Morel and Harry Hemond. Rob completed his undergraduate training in Analytical Chemistry in Durban, South Africa (RSA) and his MS at the University of Cape Town in 1983. Besides his academic studies and achievements, he has worked in research and development and for the Sea Fisheries Research Institute in Cape Town, RSA, studying oil pollution, and also completed 2 years as a program officer for the US National Science Foundation (NSF).

Rob has authored and co-authored over 230 scientific papers and book chapters, with over 27,485 citations with an H-index of 85 (Google Scholar). His four highest cited papers have more than 1000 citations each. He has co-edited four books and edited 6 special issues of journals focusing on large research activities, such as multi-investigator ocean cruises and conferences. He published the book Trace Metals in Aquatic Systems. Rob and his research group have presented papers at more than 400 national and international meetings, and he has been invited to present his research at institutions globally. Rob has attended all the International Conference on Mercury as a Global Pollutant (ICMGP) conferences, except the first conference in Sweden when he was denied a visa due to the cultural boycott against South Africans that was in place due to the continuation of apartheid. He has been a ICMGP plenary speaker on two occasions (Minamata in 2004 and Nova Scotia in 2011). He has been on the Scientific Steering Committee (SSC) for a number of the ICMGP conferences, and was an Executive Committee Member for the 2017 conference in Providence, Rhode Island, and is for the 2022 virtual meeting. He has been on the organizing committee and a SSC member for other international conferences, including the International Conference on Heavy Metals in the Environment (ICHMET), where he was a plenary speaker in 2018, and the International Estuarine Biogeochemistry Symposium (IEBS), which he hosted in 2004. He has chaired sessions at most of the ICMGP meetings and at the other conferences that he has attended.
continued below

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Prof. Rob Mason with his award in July 2022

His mentoring activities have resulted in 13 PhD and 8 MS theses, where he has been the major advisor, and he has been a committee member for many other graduate students. Eighty percent of his graduate students have been women and, besides the USA, his students have come from Africa and Asia. He has been an external examiner for PhD students in Canada, Europe and South Africa. He has also mentored more than 10 post-docs and visiting scientists from around the world, including Fulbright Scholars and students/post-docs from Europe and Asia. He has also had many high school and undergraduate students working in his laboratories over the years. He has taught classes throughout his career, and has always incorporated his research into his teaching. He expects to continue to teach classes in Chemical Oceanography, Trace Metals and Isotopes and Environmental Chemistry in the future.

He has collaborated extensively with scientists from around the world and has been involved in synthesis and other activities through national and international organizations including the United Nations Environmental Program (UNEP), and other UN organizations, and their partnership programs, the Arctic Monitoring and Assessment Program (AMAP), and the Hemispheric Transport of Air Pollutants (HTAP) initiative. He has been actively involved in communicating science to policy makers both in the USA and globally. He has been involved in many activities as a science advisor to federal, state and local organizations and industry related to contaminated sites and/or the impacts of human activities on local waters and biota, and subsequently humans and wildlife, and in their remediation.

Rob’s research has been funded by numerous federal and state agencies, as well as from non-governmental organizations, with the majority of his funding from the NSF (30 grants). He has been part of long-term studies, such as the METAALICUS Project, the GEOTRACES Program and studies on mercury in coastal environments in collaboration with colleagues at Dartmouth College. He has collaborated extensively with scientists in America, Europe, Asia and Africa. His research has taken him to the far corners of the Earth, including remote regions of the Arctic, Pacific and Atlantic Oceans. He has participated in 9 open ocean cruises during his career, and been chief scientist on more than one occasion, and has been involved in many coastal cruises and terrestrial studies. He has conducted research in Southern Africa and was also a Fulbright Scholar doing studies in West Africa related to artisanal gold mining (ASGM) impacts on the environment.

Rob recently participated in a research cruise in the Arctic Ocean and his post-doc was involved in another cruise around Iceland in 2021. He expects to continue his open ocean studies going forward, and hopes to remain involved in the GEOTRACES program. He is continuing with studies of Hg interactions in coastal waters, and the relationship between Hg cycling and transformation and those of other elements, such as selenium. He is currently the major advisor/co-advisor of 5 PhD students and is actively involved in their research, and is also actively writing papers based on prior studies. There are many papers still to be written and he is also currently involved in synthesis efforts as part of the current AMAP mercury synthesis. He expects to remain active in research, teaching, consulting and related activities for several years as there are too many good ideas to pursue to stop right now!

On the behalf of the mercury scientific community, the Scientific Steering Committee of the 15th International Conference on Mercury as a Global Pollutant, cordially congratulate Professor Mason for receiving the LAA Award.

Pieter Visscher selected as a GSA 2022 fellow

DMS is proud to announce that Prof. Pieter Visscher has been newly elected as a 2022 fellow at the Geological Society of America. The GSA Society Fellowship is an honor bestowed on the best of our profession by election at the spring GSA Council meeting. GSA members are nominated by other GSA members in recognition of a sustained record of distinguished contributions to the geosciences and the Geological Society of America through such avenues as publications, applied research, teaching, administration of geological programs, contributing to the public awareness of geology, leadership of professional organizations, and taking on editorial, bibliographic, and library responsibilities.
Congratulations, Pieter!

This is what nominator Nora Noffke said about Pieter:

"Pieter Visscher has made commendable contributions in carbon biogeochemistry, geomicrobiology, and marine sedimentology. He is active member of GSA for 25 years, and has presented regularly at GSA meetings. More so, Pieter has successfully trained many students and peers"

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Prof. Pieter Visscher doing field measurements in remote regions of Chile

Ann Bucklin leads new Ocean Decade Action: MetaZooGene

The UN Decade of Ocean Science for Sustainable Development 2021-2030 (see: https://www.oceandecade.org/) has endorsed and approved a new project led by Ann Bucklin (UConn Marine Sciences) titled, MetaZooGene: Metabarcoding Zooplankton Diversity. The new project builds off an international Working Group of the same name, MetaZooGene (see: https://metazoogene.org/), sponsored by the Scientific Committee for Oceanic Research (SCOR WG157) and chaired by Bucklin. The new project will be attached to the Ocean Decade Program, Marine Life 2030 (see: https://marinelife2030.org/) and will work toward a global vision for integrative molecular – morphological taxonomic analysis of marine zooplankton, with overarching goals to promote and facilitate DNA barcoding and metabarcoding to characterize zooplankton species biodiversity and biogeography in ocean ecosystems.

MetaZooGene_ODA_Bucklin_10June2022

Former DMS REU student Raul Flamenco on his next career plans

Reposted from UConn Today May, 17th

By Elaina Hancock. As a child, Raul Flamenco realized he was a biologist, always eager to share newly absorbed facts with his peers about birds, or lizards, or how cool tentacles are. He soon learned this zeal set him apart, which is something he was already grappling with as a Latinx student growing up in a predominantly white area of the Midwest.

Flamenco started to hide this part of himself to blend in more, which lead him to be unsure of what he wanted to do when he grew up. However, along his path in higher education and now working toward a PhD in Natural Resources, he has learned to embrace his true self and his love of studying nature.

Flamenco is a recent recipient of a National Science Foundation Graduate Research Fellowship, and of a member of UConn’s transdisciplinary training program in the Center of Biological Risk Team-TERRA.

He sat down with UConn Today to talk about his journey and his hopes for inspiring others experiencing a lack of representation.

 

Can you tell us how you rediscovered your love for animals and nature?

For a long time, I had no idea what I wanted to do. For school, I moved back to California, where I’m originally from, and I started taking classes at a community college to not spend an insane amount of money.

I knew I wanted to help people, so I started taking nursing classes, and I had to take a general biology class. I chose marine biology.

On the first day of class, the professor was so animated and passionate, and I kind of saw myself in him because he was Latino, too. It reinvigorated my love for animals, and I realized this is something that I can do, so, I changed my major to biology.

What helped you realize what you wanted to study ecotoxicology?

I was going to study marine biology because I really love invertebrates and I feel like they are underrepresented under undervalued organisms. Then I found out about ecotoxicology, which is the study of toxic chemicals and their impacts on ecosystems. Ecotoxicology is a unique union of different disciplines that benefits people and animals.

Two years before I decided to come to UConn for graduate school, I applied for a Research Experience for Undergraduates  (REU) with Penny Vlahos at Avery Point. I was selected, so I came out for 10 weeks and got to work on my own project looking at pesticides and mercury in harbor seal pup tissues to see if there was a relationship between the size of the pups compared with their pesticide or mercury contaminant burden.

What pieces of advice have been most helpful for you, and what do you tell others who may be unsure of what they want to do?

The advice that my mentors gave me was how important it is to choose the right advisor. Your advisor is the person that you are kind of stuck with, and having a good relationship with them is important to make grants or fellowships happen and to ensure that your research aligns with your interests.

I found my advisor, Jess Brandt after she had put out a call for students on Twitter. I reached out and we ended up having an interview that ended up being three and a half hours. It just kind of became a conversation and I thought that was a good indication that we’d get along and that it could be a good working relationship.

I ended up choosing UConn because of my advisor. Also having done the REU two summers prior at Avery Point, I already had an experience of Connecticut, I knew it’s not like the Midwest, it’s not like California, but somewhere in between.

I’m also a big advocate of community colleges. Through community college, I met that professor who was unforgivingly himself and seeing him talk so excitedly about what he was passionate about reminded me of how I get when I’m around the people I’m most comfortable around, I learned to not give that up.

Another difficulty in academia is imposter syndrome, and working through that has added another layer of self-discovery. I remember something that helped me in high school was a when a teacher said, “Fake it ’til you make it,” and I kind of stuck with that. Even if something’s difficult or challenging, I’ll do my best and just get through it. Now that I’m here, I’ve made it and I still feel like I’m faking it even though I’m doing research at this level and I received a prestigious NSF Fellowship sometimes I still feel like what am I really doing? Should I really be here? Based on conversations I’ve had with professors it seems like that never really goes away.

What has your experience been like as a member of Team-TERRA?

It is an interdisciplinary fellowship where we look at the risks to food, energy, water, and ecosystem services. The project is a chance for us to combine our expertise in a way that we wouldn’t normally. Two of us study birds, another studies wetlands, and I study the effects of contaminants.

We’re looking at how climate change can impact the release of contaminants into rivers through combined sewer overflows and other flooding events and how contaminants that get into rivers can then get into fish and shellfish that people are consuming.

We worked on a survey for anglers to figure out when and how much fish they eat, what species they catch. This project links things that I’m passionate about that in my normal research I’m not able to do as concretely — it’s linking contaminants to people.

That’s what interested me about ecotoxicology in the first place, I knew I wanted to help people and in this field I can help people and animals. Team-TERRA helped me bridge that gap.

What’s next?

I want to become a professor to serve as a mentor and role model for future generations of students. I am coming to understand myself better and knowing who I am and not giving in to what other people expect me to be or do. I always saw myself as kind of a chameleon, like I never really belonged anywhere, and I would just change who I was a little bit. That wasn’t so great for discovering my truest self.

Because of a professor just existing and being himself and knowing how few Latinos there are in academia, those are the driving reasons for why I want to become a professor, to become that representation that was important for me to help me get to where I am now.

I determined that getting my Ph.D. was the route that I have to take to get there and here I am.

Under Ocean Acidification, Embryos of a Key Forage Fish Struggle to Hatch

A potential ripple effect from carbon in the atmosphere could have severe impacts throughout the ocean ecosystem

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This photo shows sand lance embryos that have and have not hatched. Sand lance have trouble hatching at future ocean CO2 levels (photo courtesy of Emma Cross).


By Elaina Hancock. Reposted from UConn Today, 7 April 2022

When carbon is emitted into the atmosphere, about a quarter of it is absorbed by the earth’s oceans. As the oceans serve as a massive ‘sink’ for carbon, there are changes to the water’s pH – a measure of how acidic or basic water is. As oceans absorb carbon, their water becomes more acidic, a process called ocean acidification (OA). For years, researchers have worked to understand what effect this could have on marine life.

While most research so far shows that fish are fairly resilient to OA, new research from UConn, the University of Washington, the National Oceanic and Atmospheric Administration (NOAA), and Southern Connecticut State University, shows that an important forage fish for the Northwest Atlantic called sand lance is very sensitive to OA, and that this could have considerable ecosystem impacts by 2100. The team’s findings have just been published in Marine Ecology Progress Series 687.

Sand lance spawn in the winter months in offshore environments that tend to have stable, low levels of CO2, explains UConn Department of Marine Sciences researcher and lead author Hannes Baumann.

“Marine organisms are not living in a uniform ocean,” Baumann says. “In near shore environments, large CO2 fluctuations between day and night and between seasons are the norm, and the fish and other organisms are adapted to this variability. When we stumbled upon sand lances we suspected they are different. We thought that a fish that lives in a more open-ocean offshore environment might be more sensitive than the near-shore fish because there’s just much less variability.”

The project was a collaboration with physical oceanographers, including Assistant Professor of Marine Sciences Samantha Siedlecki and Michael Alexander from NOAA’s Physical Sciences Laboratory in Boulder, Colorado, who modeled CO2 levels in 2050 and 2100 for a specific part of the Gulf of Maine where sand lance spawn. Then Baumann and his team reared sand lance embryos in the lab under experimentally higher CO2 levels matching the projected levels.

There are instances of direct fish mortality as result of elevated CO2, but they are rare, says Baumann. However, sand lance embryos proved to be exceptionally sensitive, and fewer embryos hatched under future oceanic CO2 conditions. The researchers repeated the experiments three more times to avoid jumping to conclusions but each time they observed the same result.

“We found that embryo survival-to-hatch decreased sharply with increasing CO2 levels in the water, concluding that this is one of the most CO2-sensitive fish species studied thus far,” Baumann says.

Sand lances are surely one of the most important forage fish here on the Northwest Atlantic shelf… The humpback whales, sharks, tuna, cod, shearwaters, terns — you name it — they are all relying on sand lance.

With this interdisciplinary approach combining model forecasts and serial experimentation the researchers arrived at a picture that is much more specific.

“We consequently applied principles of serial experimentation, which is a most timely and important topic in ocean acidification research right now,” Baumann says. “Because our findings are backed up by repeated independent evidence, they are more robust than many published ocean acidification studies to date.”

In addition to preventing many sand lance embryos from developing normally, the researchers document a second negative, and novel, response to elevated CO2. Higher CO2 levels appear to make it harder for embryos to hatch.

Baumann explains the lowered pH likely renders enzymes needed for successful hatching less effective, leaving the embryos unable to break through their eggshell (chorion) to hatch.

The results show that by 2100, due to acidification, sand lance hatching success could be reduced to 71% of today’s levels. Since sand lance are such a critical component of the food web of the Northwest Atlantic, this marked decrease in sand lance would have profound impacts throughout the ecosystem.

“Sand lances are surely one of the most important forage fish here on the Northwest Atlantic shelf,” Baumann says. “Their range spans from the Mid Atlantic Bight all the way to Greenland. Where we studied them, on Stellwagen Bank, they are called the backbone of the ecosystem. The humpback whales, sharks, tuna, cod, shearwaters, terns — you name it — they are all relying on sand lance, and if sand lance productivity goes down, we will see ripple effects to all these higher trophic animals. Even though we humans don’t fish for sand lance, we need to take care of the species because it has such a huge effect on everything else.”

Baumann says this study supports the hypothesis that offshore, high latitude marine organisms like the sand lance may be among the most vulnerable to OA. As a result, these organisms and food webs will likely be impacted first and soon, and we must act now.

Previous research has focused on opportunistically chosen species when testing their sensitivity for ocean acidification, says Baumann, but this should change.

“We need strategic thinking about what species we are testing next, because we cannot test every marine fish species, that’s an impossible task. We should concentrate on fish species that are likely the most vulnerable, and therefore the ones that are probably being affected first and this research makes a compelling argument that those are the fish species at higher latitudes and in more offshore than nearshore environments.”


DMS researchers contribute to study on copepod climate adaptation

One of the most difficult challenges facing scientists is predicting how organisms will respond to rapid global change. A collaboration between oceanographers at the University of Connecticut and evolutionary biologists at the University of Vermont is looking into how copepods (tiny crustaceans that rival insects as the most abundant animals on the planet) adapt to ocean warming and acidification. This requires understanding the underlying genomic mechanisms that allow these animals to adapt, and the constraints to adaptation. This study by Reid Brennan and collaborators is a lucid example of this approach, identifying sets of genes that are linked to copepod adaptation to stressful new environments, and showing that the ability of these animals to respond to changing conditions is challenged after prolonged adaptation. Therefore, there are limits to adaptation that can constrain the resilience of animal populations to environmental stress.



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DMS faculty contributes textbook chapter on Fish Ecology

3rd March 2022. DMS faculty Hannes Baumann contributed a chapter to the new textbook Marine Biology: a functional approach to the oceans & their organisms (Taylor & Francis), which has just been published. The chapter is based on Baumann's long-running class "Ecology of Fishes" (MARN4018/5018), touching on a large variety topics including fish evolution, zoogeography, metabolism, growth, reproduction & basic concepts of fisheries science. The book is geared towards advanced undergraduate and graduate students, stimulating interest while encouraging readers to seek out further in-depth sources.



"With about 28,000 known species, fishes make up more than half of all known vertebrates (Helfman et al. 2009). Over the course of their long evolutionary history they radiated in every conceivable aquatic habitat, from the open ocean and deep-sea trenches to shelf seas, estuaries and lakes, to rivers and the smallest streams and ponds. They are found in subzero Antarctic waters, altitudes of over 4,000 m and even acidic desert springs of > 40°C (Moyle and Cech 2004). The fascinating adaptations to these habitats have produced a mind-bending diversity of form and function, a difference in size that spans more than three magnitudes (0.01 – 18 m), and a profusion of reproductive strategies. Apart from their diversity and unique evolutionary history, fishes are of intense scientific interest for economic reasons, because they comprise the nutritional foundation for a large part of humanity (Costanza et al. 1997) and their exploitation over time has led to thriving – and warring – civilizations. Today, the impetus of sustainable fish management at a time of rapid ecological re-organization due to man-made climate change has made the study of fish ecology and fish stock productivity as urgent and important as ever."


Fig01--systematics
Fig.1: Origin, evolution, and systematics of fishes. A – Origin hypothesis. Early during chordate evolution, sessile arm feeders (pterobranchs) gave rise to gill feeders. In one line, free-swimming filter-feeding larvae lost their sessile stage and evolved into the first, gill-feeding vertebrates (redrawn after Romer and Parsons 1977). B – Evolution and relative abundance of major fish lines through time. Most of today’s fish groups originated in the Devonian; ray-finned fishes became the dominant fish group during the Meso- and Cenozoic (numbers refer to million year ago, Mya). C – Abridged overview of Actinopterygii systematics showing select major orders (-formes) and Perciform families (-idae) sorted top to bottom from ancestral to most derived groups. Most fishes are Teleosts, and within those, most belong to the Euteleosts. Acanthopterygii evolved fin spines; the most species-rich vertebrate order are the Perciformes (after Moyle and Cech 2004).